We propose a noise suppression method using a feed forward circuit for injection-seeded WDM-PON. The required injection power is reduced by 8 dB by employing the proposed method. We investigate the limiting factors by tracing the relative intensity noise in the injection-seeded WDM-PON. Interplay of two filtering effects determines the net suppression of noise.
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A new nanoprojection lithography (NPL) is proposed to manufacture plasmonic nanogratings. Here, low-cost self-assembly elastomeric polydimethylsiloxane wavy structures are used as the interference modules, with their periods and amplitudes largely controlled by the applied mechanical strain in the synthesis process. Well-defined plasmonic grating couplers with desired feature sizes and wavelengths...
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Over-coupled microdisk resonators with high intrinsic quality factors are proposed as compact and low-insertion-loss delay lines for narrowband optical filters. Design challenges including dealing with the multimode nature of the microdisk resonator and achieving a strong coupling to the selected mode are addressed. Employing the microdisk-based delay line, we demonstrate a compact first-order tun...
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A novel type of hybrid plasmonic waveguiding structure that integrates semiconductor and metallic nanowires has been proposed and investigated at telecommunication wavelengths. Semiconductor nanowires symmetrically placed on both sides of a metallic nanowire provide an additional degree of freedom for tuning the characteristics of the plasmonic nanowire mode. Theoretical analysis reveals that at a...
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We investigate a carrier phase estimation algorithm for the polarization-switched quadrature phase-shift-keying modulation format. The algorithm, which is based on the conventional block Mth power feed-forward scheme, works jointly on both polarizations and shows a significant performance improvement compared with a polarization-independent scheme. We evaluate the tolerance to laser pha...
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The spectral-amplitude-coding optical code-division multiple-access (SAC-OCDMA) technique is a vital candidate for future optical networks. Until now, there has been no exact analysis for the performance of systems using these techniques, and most researchers use upper and/or lower bounds to obtain the bit-error rate (BER) of these systems. In this letter, a more accurate analysis of the statistic...
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A spatial resolution of 10 cm was obtained for distances of 60~80 km in different field environments using phase-noise-compensated optical frequency domain reflectometry. The outstanding spatial resolution makes it possible to identify high-birefringence sections along installed cables. In field trials, we successfully observed beat lengths as small as ~20 cm, which showed that there were very lar...
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We derive an analytical solution for the differential gain in Brillouin optical time-domain analysis. The found solution gives insight into the mechanisms leading to the high-spatial and spectral resolution observed in differential schemes. An experimental test has been carried out to validate the analytical solution.
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In this letter, self-assembled polystyrene nano-spheres with a diameter of 193 nm were used to fabricate the 3-D colloidal-photonic-crystal (CPC) bottom reflector for blue GaN-based light-emitting diodes (LEDs). Experimentally, the key point is the hydrophilic treatment of substrate and immediately to disperse the suspension into the substrate at 30 °C. The equilibrium between the particle ...
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A simplified full-duplex 60-GHz optical millimeter-wave access system is proposed and experimentally demonstrated with a 16-QAM-OFDM downlink generated by selected mapping (SLM). The system receiver is realized with optical heterodyne detection and electrical self-mixing down-conversion. In the experiment, 5-Gb/s 16-QAM-OFDM signals are transmitted over 42-km SMF-28 and a 0.4-m wireless channel. T...
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A novel photonic crystal fiber (PCF) with a single core, rather than two cores, for wavelength splitting application has been proposed through the full-vector finite-element method. The light located in the 1.31- and 1.55- μm bands propagates through orthogonal polarization states in the proposed fiber. For a propagation distance of 20 mm, the 20-dB bandwidth for the same x- or y-polarized ...
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A TE-TM mode converter fabricated in a single trench SiON waveguide is described. The device has the advantage that only single masking and etching process is needed to fabricate it. We discuss the design of the mode converter from the view point of fabrication tolerance. The single trench structure is fabricated using the reactive ion-etch lag phenomenon. A 97% TE-TM mode conversion (extinction r...
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In this letter, a Mach-Zehnder-based four-port switching module was designed and fabricated by a 0.8-μm standard commercial complementary metal-oxide semiconductor line. The module is composed of five electro-optic switching elements and can be used to realize nonblocking switching for the duplex interconnection among four ports. The switching elements are electrically driven with a nanosec...
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Optical generation and transport of ultra-wideband (UWB) pulses extends the reach of these weak signals to several kilometers by exploiting passive optical networks. At the remote node, the UWB transmitter should be low cost and compact in size for indoor communications. We propose and experimentally demonstrate an integrated solution based on a racetrack micro-ring resonator in silicon-on-insulat...
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An all-optical wavelet transformer used to analyze a high-speed and broadband electrical signal is proposed and demonstrated for the first time to our knowledge. The wavelet transform is implemented based on a temporal pulse shaping system incorporating a 2-D array of cascaded linearly chirped fiber Bragg gratings (LCFBGs). An electrical signal to be analyzed is applied to a Mach-Zehnder modulator...
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In this letter, we demonstrate the decoding stability of an optical hybrid filter (OHF) node module for an adaptive network to an environment temperature fluctuation. [Error free] signal decoding was observed from a temperature range of 0° to 60°. Improving athermal mounting technology would expand the applicable temperature range of an OHF node module as the passive node.
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We demonstrate the generation of a spectrally flat continuous wave supercontinuum by pumping deep in the normal dispersion region. A Raman cascade forms up to the anomalous dispersion region, where modulation instability supercontinuum dynamics are initiated. The Raman cascade seeds the frequency up-shifted part of the continuum, leading to a spectral flatness of 5 dB from 1.15 to 2.15.
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A real-time 1.25-Gb/s transmission over a 50-m step-index plastic optical fiber (SI-POF) with -12.5-dBm sensitivity at bit error rate equal to 10-9 was achieved. The binary modulated signal was received and post-equalized using a fully integrated optical receiver. A green edge-emitting laser diode with 520 nm is used, which gives a lower attenuation over POF compared to the traditional ...
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Aims & Scope

IEEE Photonics Technology Letters addresses all aspects of the IEEE Photonics Society Constitutional Field of Interest with emphasis on photonic/lightwave components and applications, laser physics and systems and laser/electro-optics technology.